The present invention relates to an apparatus for checking axial dimensions, such as the overall length of a workpiece or the length of a portion of a workpiece, particularly of shafts, axles, hubs, and the like. More particularly, the invention is directed to an axial dimension checking apparatus of the type which includes a base element and structures for accommodating measuring devices and workpieces which are to be checked.
To check axial dimensions on workpieces, such as shafts, axles, hubs, and the like, apparatuses are known in which a base element is configured as a base plate or base frame onto which the measuring devices are mounted. The measuring devices mounted on the base element may include guide elements or a guide rod and length measurement sensors with offset sensor tips.
Depending on the number of axial measurements to be checked, the required axial orientation of such measuring devices and their often-considerable structural lengths makes it necessary to arrange several measuring devices next to one another.
Since, however, the number of measuring devices that can be combined and assembled in this way is limited, a suitable sensor tip must be selected or adapted, depending on the spacing of the individual measuring devices, to the face or surface of the workpiece which it is to check. A particular drawback of such apparatuses is the bridging of the spaces between the measuring devices and the faces to be checked if the workpiece to be measured exhibits considerable, sudden changes in diameter, as is frequently the case with drive shafts. Since customarily the positions in which the measuring devices are arranged in the assembly depend on the largest diameter of the workpiece, the sensor tips must therefore be able to extend to the portions where the smallest diameters start.
To accommodate and hold the workpieces to be measured, such apparatuses are often equipped with guide strips on which spindle sleeve mounts or props are assembled which, however, are completely independent of the configuration of the measuring devices.